Blood pulse, cardiac pulse / Pulsations cardiaques

Recognition using the blood pulse shape or the electrocardiogram has been proposed, but there was low activity on this subject until 2013 when a product was announced.

La reconnaissance par la forme du pouls sanguin ou de l'électrocardiogramme a été proposé, mais il n'y avait que peu d'activité dans ce domaine jusqu'en 2013, lorsque qu'un produit a été annoncé.


Pulse reading

Pulse reading is performed using the same material than pulse oxymetry, with two LEDs and a photodiode, to read the blood pulse shape. One LED is enough if you just want to acquire the blood pulse.

capteur de pouls pour oxymétrie oximeter exemple d'oxymètre waveform
A pulse oxymeter / Un oxymètre de pouls
Blood pulse waveform / forme d'onde du pouls

La lecture s'effectue avec le même matériel que pour l'oxymétrie par le pouls, à l'aide de 2 DEL et d'une photodiode. Une seule DEL suffit si vous voulez juste acquérir le pouls.


Electrocardiogram / ECG / EKG

Everyone knows how a regular EKG is done, using several electrodes, close to the heart.

But the minimum requirement to acquire an EKG is form a loop with the heart, for instance between the two hands. Electrodes at the end of a finger is not enough.

Search for "handheld ECG" for more info.

EKG

On connait généralement la manière de réaliser un ECG, avec des électrodes disposées plutôt près du coeur. Mais il faut au minimum 2 électrodes et former une boucle dans le corps, par exemple en utilisant les deux mains. Au bout d'un doigt, il n'y a pratiquement pas de signal.


Wave radar

“Cardiac Scan” is a radar-based system that can identify the exact shape of a heart.

Press release fron Buffalo university

A novel continuous authentication system, namely Cardiac Scan, based on geometric and non-volitional features of the cardiac motion is presented. Cardiac motion is an automatic heart deformation caused by self-excitement of the cardiac muscle, which is unique to each user and is difficult (if not impossible) to counterfeit. Cardiac Scan features intrinsic liveness detection, unobtrusiveness, cost-effectiveness, and high usability. We prototype a remote, high-resolution cardiac motion sensing system based on the smart DC-coupled continuous-wave radar. Fiducial-based invariant identity descriptors of cardiac motion are extracted after the radar signal demodulation.

cardiac waveradar

Laser

MIT Technology Review reports that the Pentagon now has a prototype infrared laser that can identify people by their heartbeat. It is called “Jetson” and uses laser vibrometry to detect movements on the surface of the skin caused by a person’s pulse. It even works from as far as 200 meters away.
There are some caveats though. While the laser can detect a heartbeat from a distance on bare skin or through thin material like a tee shirt, thicker clothing like a jacket makes it ineffective. The system also needs about 30 seconds to create a good enough profile for analysis. The subject must be still during that time as well.


General info

There are many papers related to identification using ECG. Here are some starting papers:


Proposed systems